A British man sentenced to death by a Russian court has been told his execution will take place, his family says.

Aiden Aslin and Shaun Pinner were convicted by a court that is not internationally recognized, in the so-called Donetsk People's Republic (DPR).

And as the BBC writes, the Telegraph reports, Aslin told his family that his captors said there had been no attempt by UK officials to negotiate on his behalf.

Aslin's family said they had spoken to him in a phone call in which he said they had been told "time is running out" by his captors.

Aiden Aslin (right) and Shaun Pinner (left) were both captured during fighting in Mariupol

"No words, just no words, it must be everyone's worst nightmare to threaten a member of your family this way," Aslin's grandmother Pamela Hall was quoted as saying by the BBC.

"Aiden was extremely upset when he called his mother this morning.

"In the end, Aiden said the DPR told him that no one from the UK had contacted him and that he would be executed."

"I have to believe what Aiden told us, that if the DPR does not get an answer, then they will execute him.

"Of course I hope this is not true."

It is about two people who were caught after spending weeks defending the besieged city of Mariupol.

But the court with Russian prosecutors called them "mercenaries", accusing them of being sent to fight in a foreign money conflict.

Aiden Aslin (left) and Shaun Pinner

They were charged with crimes, including violent seizure of power, and undergoing training to carry out terrorist activities, according to RIA Novosti.

Earlier this month, Ukrainian President Volodymyr Zelensky told British students that what Russia was doing to the British couple was a "tragic vice" and that "there can be no justification for such actions."

He said it was "a very strong and dangerous signal" to other countries that Russia "is acting in this way towards the citizens of every country".

On the other hand, the UK Government has said that they should be treated as prisoners of war according to the laws set out in the Geneva Conventions.

Meanwhile, the British Foreign Secretary discussed his case with Ukraine earlier in June.

Liz Truss said she and her Ukrainian counterpart Dmytro Kuleba had spoken of "efforts to secure the release of prisoners of war held by Russian representatives" and called the death sentences a "false trial with absolutely no legitimacy".

But UK government sources indicate that the ministers are currently unwilling to negotiate directly with Russia, as this could risk inciting a false Russian narrative that the men are mercenaries.